Current inputs interface for an electrical device

ABSTRACT

According to an aspect of the present disclosure, an electrical power meter, is disclosed. The electrical power meter includes a housing for containing electrical circuitry therein, the housing including at least one of voltage and current inputs, the housing including passages extending entirely therethrough, wherein the passages are configured to receive a CT lead therethrough, and wherein the CT leads are not electrically connected to the electrical circuitry therein; and a face plate operatively supported on a surface of the housing, wherein the face plate includes at least one of displays, indicators and buttons. It is envisioned that the through passages are located along a side of the housing.

This application is a continuation application of U.S. application Ser.No. 11/003,064, filed Dec. 3, 2004, entitled “Current inputs interfacefor an electrical device”, the contents of which are incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION

1. Technical Field

The present disclosure relates to electrical devices and/or power metersand, more particularly, to electrical devices, including electricalpower meters, having current input interfaces.

2. Background of Related Art

Electric utility companies track electric usage by customers by usingpower meters. These meters track the amount of power consumed at aparticular location. These locations range from power substations, tocommercial businesses, to residential homes. The electric utilitycompanies use the power meter to charge its customers for their powerconsumption, i.e. revenue metering.

A popular type of power meter is the socket-type power meter. As itsname implies, the meter itself plugs into a socket for easyinstallation, removal and replacement. Other meter installations includepanel mounted, switchboard mounted, and circuit breaker mounted.Typically the power meter connects between utility power lines supplyingelectricity and a usage point, namely a residence or commercial place ofbusiness. Though not typical, a power meter may also be placed at apoint within the utility's power grid to monitor power flowing throughthat point for distribution, power loss, or capacity monitoring. Also,power meters can be used to monitor internal customer usage that handlesubmetering functions.

Traditionally, power meters used mechanical means to track the amount ofconsumed power. The inductive spinning disk power meter is stillcommonly used. The spinning disk drives mechanical counters that trackthe power consumption information.

Newer to the market are electronic power meters. Electronic meters havereplaced the older mechanical meters, and utilize digital sampling ofthe voltage and current waveforms to generate power consumptioninformation. In addition to monitoring power consumption, electronicmeters can also monitor and calculate power quality, that is, voltage,current, real power, reactive power, and apparent power, among others.These power quality measurements and calculations are displayed on anoutput display device on the meter.

In more recent developments, limited power consumption information canbe transmitted from the power meter to the utility through the use oftelephone communications circuitry contained either within or externalto the meter. These developments are advantageous to the utility companyin that it reduces the need for employees being dispatched to the remotelocations to collect the power consumption information. A standard modemreceives raw power consumption information from the power meter andtransmits the information to the utility company via telephone lines.While this represents an improvement over past techniques, thisinformation then must be interpreted and further processed to calculatethe amount of power consumption, a secondary process that results infurther processing apparatus and software, and further resulting inincreases to the costs and complexities of the overall system.

There is therefore a need for an electronic power meter that includesimproved current inputs to facilitate new installation and/orreplacement of such electronic power meters.

There is a further need for an electronic power meter that can beinstalled in a number of different configurations and/or a number ofdifferent wiring schemes.

SUMMARY

In accordance with the present disclosure, electrical devices andelectrical power meters are provided. According to an aspect of thepresent disclosure, an electrical device, includes a housing forcontaining electrical circuitry therein, the housing including at leastone of voltage and current inputs, the housing including passagesextending entirely therethrough, wherein the passages are configured toreceive a CT lead therethrough; and a face plate operatively supportedon a surface of the housing.

The electrical device may further include at least one elongate,electrically conductive plate configured for selective positioningwithin the passages of the housing. Desirably, each plate includes afirst end and a second end extending from the passages of the housingwhen the plates are positioned therein. In one embodiment, the platesmay be fabricated from nickel plated brass.

Desirably, each end of the plate is configured for selective connectionof a lug of a CT lead thereto. Alternately, each end of the plate isconfigured for selective connection of a friction fit connector of a CTlead thereto.

It is envisioned that the through passages may be located along a sideof the housing. Desirably, the CT leads are not electrically connectedto the electrical circuitry within the housing.

Desirably, the electrical device is configured for ANSI and DINmounting. The electrical device is capable of connection as at least oneof a three-phase, four-wire system wye with direct voltage, 3 element; athree-phase, four-wire system wye with direct voltage, 2.5 element; athree-phase, four-wire wye with PTs, 3 element; a three-phase, four-wirewye with PTs, 2.5 element; a three-phase, three-wire delta with directvoltage; and a three-phase, three-wire delta with PTs.

In one embodiment, at least one of a top surface and a bottom surface ofthe housing is configured to selectively receive a mounting bracket. Theface plate may include at least one of displays, indicators and buttons.

According to another aspect of the present disclosure, an electricalpower meter, is disclosed. The electrical power meter includes a housingfor containing electrical circuitry therein, the housing including atleast one of voltage and current inputs, the housing including passagesextending entirely therethrough, wherein the passages are configured toreceive a CT lead therethrough, and wherein the CT leads are notelectrically connected to the electrical circuitry therein; and a faceplate operatively supported on a surface of the housing, wherein theface plate includes at least one of displays, indicators and buttons. Itis envisioned that the through passages are located along a side of thehousing.

The electrical power meter further includes an elongate, electricallyconductive plate configured for selective positioning within thepassages of the housing. Desirably, each plate includes a first end anda second end extending from the passages of the housing when the platesare positioned therein. The plates may be fabricated from nickel platedbrass.

Desirably, each end of the plate is configured for selective connectionof a lug of a CT lead thereto. Alternately, each end of the plate isconfigured for selective connection of a friction fit connector of a CTlead thereto.

Desirably, the electrical power meter is configured for ANSI and DINmounting. The electrical power meter is configured for connection as atleast one of a three-phase, four-wire system wye with direct voltage, 3element; a three-phase, four-wire system wye with direct voltage, 2.5element; a three-phase, four-wire wye with PTs, 3 element; athree-phase, four-wire wye with PTs, 2.5 element; a three-phase,three-wire delta with direct voltage; and a three-phase, three-wiredelta with PTs.

Desirably, at least one of a top surface and a bottom surface of thehousing is configured to selectively receive a mounting bracket.

According to yet another aspect of the present disclosure, a method ofinstalling an electrical power meter to a panel, in provided. The methodincludes the steps of providing an electrical power meter. Theelectrical power meter includes a housing for containing electricalcircuitry therein, the housing including at least one of voltage andcurrent inputs, the housing including passages extending entirelytherethrough, wherein the passages are configured to receive a CT leadtherethrough and wherein the CT leads are not electrically connected tothe electrical circuitry therein. The housing is configured for bothANSI and DIN installations. The electrical power meter further includesa face plate operatively supported on a surface of the housing, whereinthe face plate includes at least one of displays, indicators andbuttons, and mounting means operatively associated with the electricalpower meter for securing the electrical power meter to a panel.

The method further includes the steps of inserting a rear end of thehousing into an aperture formed in a panel; at least one of passing CTleads through the passages formed in the housing and terminating CTleads to conductive plates disposed in the passages of the housing; andsecuring the mounting means of the electrical power meter to the panel.

Desirably, the electrical power meter includes at least one elongate,electrically conductive plate configured for selective positioningwithin the passages of the housing. Each plate includes a first end anda second end extending from the passages of the housing when the platesare positioned therein and configured for selective engagement with CTleads.

In one embodiment, the mounting means of the electrical meter includesthreaded rods extending from the face plate and positioned for insertioninto corresponding holes formed in the panel. In another embodiment, themounting means includes brackets selectively engagable with the housingof the electrical meter.

Desirably, the electrical power meter may be configured for connectionas at least one of a three-phase, four-wire system wye with directvoltage, 3 element; a three-phase, four-wire system wye with directvoltage, 2.5 element; a three-phase, four-wire wye with PTs, 3 element;a three-phase, four-wire wye with PTs, 2.5 element; a three-phase,three-wire delta with direct voltage; and a three-phase, three-wiredelta with PTs.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and features of the presently disclosed electricaldevice, e.g., electronic power meter, will become more readily apparentand may be understood by referring to the following detailed descriptionor illustrative embodiments taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a perspective view of an electrical device in accordance withthe present disclosure;

FIG. 2 is a top plan view of the electrical device of FIG. 1;

FIG. 3 is a side elevational view of the electrical device of FIGS. 1and 2;

FIG. 4 is a rear perspective view of the electrical device of FIGS. 1-3illustrating the connection of lead terminals thereto, in accordancewith a method of the present disclosure;

FIG. 5 is a rear perspective view of the electrical device of FIGS. 1-3illustrating the connection of lead terminals thereto, in accordancewith another method of the present disclosure;

FIG. 6 is a rear perspective view of the electrical device of FIGS. 1-3illustrating the connection of lead terminals thereto, in accordancewith yet another method of the present disclosure;

FIG. 7 is a rear perspective view of the electrical device of FIGS. 1-3illustrating the connection of power supply and voltage inputs thereto,in accordance with a method of the present disclosure;

FIGS. 8A-8F illustrate several exemplary electrical connection diagramsfor the electrical device of FIGS. 1-3;

FIGS. 9A and 9B illustrate an ANSI installation of the electrical deviceof FIGS. 1-3;

FIGS. 10A and 10B illustrate a DIN installation of the electrical deviceof FIGS. 1-3;

FIG. 11A is a diagram of a power meter according to the presentinvention; and

FIG. 11B illustrates a coupling device of the power meter of FIG. 11 forcoupling the power meter to an electrical power line to protect thepower meter from excessive current.

DETAILED DESCRIPTION OF THE EMBODIMENT

Three-phase power is most commonly used in situations where largeamounts of power will be used because it is a more effective way totransmit the power and because it provides a smoother delivery of powerto the end load. There are two commonly used connections for three-phasepower, a wye connection or a delta connection.

As used herein and as is typical in the art, a “wye connection” isunderstood to have a phase relation and a winding relationship betweenthe phases which substantially approximates the look of a wye (“Y”). Ina wye connection or service, the neutral (or center point of the wye) istypically grounded. This leads to common voltages of 208/120 and 480/277(where the first number represents the phase-to-phase voltage and thesecond number represents the phase-to-ground voltage). The threevoltages are separated by 120° electrically. Under balanced loadconditions with unity power factor, the currents are also separated by120°.

As used herein and as is typical in the art, a “delta connection” isunderstood to have load windings which are connected from phase-to-phaserather than from phase-to-ground.

Embodiments of the present disclosure will be described in detail hereinbelow with reference to the accompanying drawings. In the followingdescription, numerous specific details are set forth to provide a morethorough understanding of the present disclosure. It will be apparent,however, to one skilled in the art that the present disclosure may bepracticed without these specific details. In other instances, well knownfunctions or constructions have not been described so as not to obscurethe present disclosure.

Referring initially to FIGS. 1-3, an electrical device, e.g., anelectronic power meter, in accordance with an embodiment of the presentdisclosure, is generally designated as 100. As seen in FIGS. 1-3,electrical device 100 includes a housing 102 defining a front surface102 a, a rear surface 102 b, a top surface 102 c, a bottom surface 102d, a right side surface 102 e, and a left side surface 102 f. Electricaldevice 100 includes a face plate 104 operatively connected to frontsurface 102 a of housing 102.

Face plate 104 includes displays 106, indicators 108 (e.g., LEDs and thelike), buttons 110, and the like providing a user with an interface forvisualization and operation of electrical device 100. For example, asseen in FIG. 1, face plate 104 of electrical device 100 includes analogand/or digital displays 106 capable of producing alphanumericcharacters. Face plate 104 includes a plurality of indicators 108 which,when illuminated, indicate to the user the “type of reading”, the “% ofload bar”, the “parameter designation” which indicates the reading whichis being displayed on displays 106, a “scale selector” (e.g., Kilo orMega multiplier of Displayed Readings), etc. Face plate 104 includes aplurality of buttons 110 (e.g., a “menu” button, an “enter” button, a“down” button, a “right” button, etc.) for performing a plurality offunctions, including and not limited to: viewing of meter information;enter display modes; configuring parameters; performing re-sets;performing LED checks; changing settings; viewing parameter values;scrolling parameter values; and viewing limit states.

As seen in FIGS. 4-7, housing 102 includes voltage connections or inputs112 provided preferably on rear surface 102 b thereof, and currentinputs 114 provided preferably along right side surface 102 e thereof.Desirably, a connector 116 or the like may be used to connect powersupply lines 118 a and/or voltage supply lines 118 b to voltage inputs112. In particular, as seen in FIG. 7, power supply lines 118 a andvoltage supply lines 118 b are electrically connected to connector 116which is, in turn, electrically connected to voltage inputs 112. Powersupply lines 118 a and voltage supply lines 118 b are electricallyconnected to internal components, circuitry and/or printed circuitboards (not shown) of electrical device 100.

As seen in FIG. 2, housing 102 includes a series of pass-throughs orapertures 120 formed along right side surface 102 e thereof andextending desirably between top surface 102 c and bottom surface 102 dthereof. While apertures 120 are shown and described as being formedalong right side surface 102 e of housing 102 it is envisioned andwithin the scope of the present disclosure for apertures 120 to beformed along any side of housing 102. As will be described in greaterdetail below, apertures 120 enable connection of electrical device 100according to a first method, e.g., a “CT (Current Transformer) PassThrough” method.

As seen in FIG. 3, electrical device 100 may include a plurality of“gills” 130 configured and dimensioned to extend through each aperture120 of housing 102. Gills 130 are desirably elongate electricallyconductive plates or bars having a first end 130 a and a second end 130b. As will be described in greater detail below, gills 130 allow for CTleads to be terminated on electrical device 100. Desirably, gills 130are fabricated from nickel plated brass.

Turning now to FIG. 4, a method of connecting electrical device 100according to the “CT Pass Through” method is shown and described.Connection of electrical device 100 according to the “CT Pass Through”method typically requires passage of CT lead(s) 10 through apertures 120of housing 102. Accordingly, CT lead(s) 10 pass directly thoughelectrical device 100 without any physical termination on electricaldevice 100. Extending CT leads 10 to electrical device 100 according tothe “CT Pass Through” method insures that electrical device 100 cannotbe a point of failure on the circuit.

Turning now to FIG. 5, an alternate method of connecting electricaldevice 100 is shown and described. As seen in FIG. 5, gills 130 havebeen inserted into apertures 120 formed in housing 102. Desirably, firstends 130 a of gills 130 are exposed along top surface 102 c of housing102 and second ends 130 b of gills 130 are exposed along bottom surface102 d of housing 102. In this manner, CT leads 10 may be electricallyconnected to first ends 130 a of gills 130 and/or second ends 130 b ofgills 130. Desirably, CT leads 10 are provided with an “O” or “U” lug 12at a free end thereof for terminating CT leads 10 to gills 130. Forexample, a screw 14 or the like may be used to connect lug 12 of CT lead10 to gill 130. As seen in FIG. 5, by terminating CT leads 10 to gills130 of electrical device 100, the possibility of a point of failureoccurring at electrical device 100 is eliminated.

As seen in FIG. 6, according to an alternate method, lugs 12 may bereplaced by friction fit quick connectors 16. Accordingly, in use, CTleads 10 may be terminated and/or electrically connected to gills 130 bysliding quick connectors 16 over the tips of first and second ends 130a, 130 b of gills 130.

In each of the embodiments above, CT leads 10 either extend throughhousing 102 of electrical device or terminate on gills 130 which areun-connected to any electrical component of electrical device 100.Unlike the embodiments disclosed herein, other electrical device (e.g.,electrical meters) utilize terminal blocks to pass the current,traveling through the CT leads, through a soldered connection on aprinted circuit board. Accordingly, the prior art electrical devices maybe susceptible to burn-out or failure in the event of a surge in currentthrough the CT leads.

Turning now to FIGS. 8A-8F, various electrical connection diagrams forthe connection of electrical device 100, are shown and described. Withreference to FIG. 8A, a connection diagram for a three-phase, four-wiresystem wye with direct voltage, 3 element, is shown. With reference toFIG. 8B, a connection diagram for a three-phase, four-wire system wyewith direct voltage, 2.5 element, is shown. With reference to FIG. 8C, aconnection diagram for a three-phase, four-wire wye with PTs (“PotentialTransformers”), 3 element, is shown. With reference to FIG. 8D, aconnection diagram for a three-phase, four-wire wye with PTs (“PotentialTransformers”), 2.5 element, is shown. With reference to FIG. 8E, aconnection diagram for a three-phase, three-wire delta with directvoltage, is shown. With reference to FIG. 8F, a connection diagram for athree-phase, three-wire delta with PTs, is shown.

Electrical device 100 may include a digital sampler for sampling avoltage and a current at a sampling point, and a processor forprocessing at least one of the sampled voltage and the sampled current.Exemplary embodiments of a digital sample and processor are disclosed inU.S. Pat. No. 6,751,563, the entire contents of which are incorporatedherein by reference.

Electrical device 100 may include an auto-calibration feature and a dataacquisition node for measuring the power usage and power quality ofelectrical power in an electrical power distribution network. Exemplaryembodiments of an auto-calibration feature and a data acquisition nodeare disclosed in U.S. Pat. No. 6,735,535, the entire contents of whichare incorporated herein by reference.

Portions of U.S. Pat. No. 6,735,535 will be reproduced here. Referringto FIG. 11A, there is shown an exemplary diagram of a power meter forcalibrating voltage and current inputs according to the principles ofthe present invention. The power meter is designated generally byreference numeral 1100 and includes a plurality of voltage input lines1102, Vin, for receiving N voltage inputs which are optically isolatedby a respective optical isolator 1104, as known in the art, to protectthe power meter 1100. The N voltage inputs are received from therespective optical isolators 1104 by a respective sample and holdcircuitry 1106 (S/H 1). Based on a control signal, the N voltage outputsof the respective sample and hold circuitry 1106 are transmitted to afirst multiplexor 108. The first multiplexor 1108 receives a controlsignal (SIGNAL 2) from a DSP 1110 to output at least one of the Nvoltage outputs received from the respective sample and hold circuitry1106. The voltage output from the first multiplexor 1108 is received bya first analog-to-digital converter 1114 which converts the analogvoltage output signal to a digital voltage signal. The digital voltagesignal is subsequently transmitted to the DSP 1110.

The power meter 1100 also includes a plurality of current input lines1120, lin, which receive N current inputs which are sampled throughrespective current transformers CT. The N current inputs are transmittedto a respective amplifier 1122 and then to respective sample and holdcircuitry 1124 (S/H 2). Based on control signal (SIGNAL 1), the sampleand hold circuitry 1124 transmits the N current inputs to the firstmultiplexor 1108. Subsequently, based on control signal (SIGNAL 2), thefirst multiplexor 1108 outputs a current output to the firstanalog-to-digital converter 1114, which is subsequently transmitted tothe DSP 1110.

The N voltage inputs and N current inputs are also received by a secondmultiplexor 1126 and at least one voltage input and at least one currentinput are transmitted to a second analog-to-digital converter 1128 basedon the control signal (SIGNAL 2). The outputs from the secondanalog-to-digital converter 1128 are transmitted to the DSP 1110. TheDSP 1110 is connected to peripherals, such as a keyboard 1130, a display1132, a modem 1134, and a network card interface 1136 for communicatingwith the power meter 1100 from a remote station (not shown), preferablythrough a network connection.

The digital representation of each of the N voltage and N current inputsis processed and stored within the DSP 1110. The DSP 1110 includes atleast a random access memory (RAM) and a read only memory (ROM).

Referring to FIG. 11B, there is shown a coupling device for sampling theN current inputs while protecting the power meter 1100 from excessivecurrent. The input and output currents lin, lout are connected via aU-shaped metal rod 1200, which is preferably ¼ inch thick, that bearscurrent for the input current signal lin. The current of the inputcurrent signal In is measured via a toroid sensor 1202 attached to atoroid 1204. The toroid 1204 is implemented to preferably convert theinput current to a proportional voltage. The U-shaped metal rod 1200traverses through the toroid 1204 for the input current signal lin, asnoted above. The metal rod 1200 also acts as a primary winding having asingle turn and the toroid 1204 acts as the secondary winding. Thetoroid 1204 preferably contains approximately 1000 turns.

Electrical device 100 may be a revenue grade meter having high speedtransient detection, such as the meter disclosed in U.S. Pat. No.6,636,030, the entire contents of which are incorporated herein byreference.

Electrical device 100 is configured and dimensioned for installationusing a standard ANSI C39.1 (4″ round) or an IEC 92 mm DIN (Square)form.

FIGS. 9A and 9B illustrate and describe a method of installingelectrical device 100 according to ANSI standards. As seen in FIGS. 9Aand 9B, face plate 104 includes mounting means in the form of aplurality of threaded rods 106 extending from a rear surface 104 athereof. Electrical device 100 is inserted into an opening or aperture“A” of panel “P” such that threaded rods 106 extend through holes “H”formed in panel “P”. Electrical device 100 is secured to panel “P” bytightening a lock washer “L” and nut “N” onto each threaded rod 106.Preferably, a mounting gasket “G” is disposed in rear surface 104 a offace plate 104 prior to the mounting of electrical device 100 to panel“P”.

FIGS. 10A and 10B illustrate and describe a method of installingelectrical device 100 according to DIN standards. As seen in FIGS. 10Aand 10B, electrical device 100 is inserted into opening or aperture “A”of panel “P” and mounting means, in the form of mounting brackets 108,are operatively connected to top surface 102 c and bottom surface 102 dof housing 102. Electrical device 100 is then secured to panel “P” usingscrews “S” extending through mounting brackets 108 and engaging thesurface of panel “P”.

Turning back to FIG. 4, electrical device 100 may include a firstinterface or communication port 150 for connection to a master and/orslave device. Desirably, first communication port 150 is situated inrear surface 102 b of housing 102. Electrical device 100 may alsoinclude a second interface or communication port 152 situated on faceplate 104 (see FIG. 1).

While the disclosure has been particularly shown and described withreference to a preferred embodiment, it will be understood by thoseskilled in the art that various modifications in form and detail may bemade therein without departing from the scope or spirit of thedisclosure. Accordingly, modifications, such as those suggested above,but not limited thereto are to be considered within the scope of thepresently disclosed electrical device.

1-29. (canceled)
 30. An electrical power meter comprising: a housing for containing electrical circuitry for measuring power usage therein, the housing including at least one voltage input and at least one current input, the at least one current input being configured as at least one passage extending entirely through the housing, wherein the at least one passage is configured to receive at least one CT lead therethrough, and wherein said at least one CT lead extends through the at least one passage of the housing un-connected to any electrical component of said electrical circuitry for measuring power usage.
 31. The electrical power meter according to claim 30, further comprising a face plate operatively supported on a surface of the housing, wherein the face plate includes at least one of displays, indicators and buttons.
 32. The electrical power meter according to claim 30, further comprising a face plate operatively supported on a surface of the housing, wherein the face plate includes a plurality of indicators configured to indicate a percentage of load bar measured by the electrical power meter.
 33. The electrical power meter according to claim 30, further comprising at least on elongate, electrically conductive plate configured for selective positioning within the at least one passage of the housing, wherein each plate includes a first end and a second end extending from the at least one passage of the housing when the plates are positioned therein.
 34. The electrical power meter according to claim 33, wherein each end of the at least one plate is configured for selective connection of a lug of a CT lead thereto.
 35. The electrical power meter according to claim 33, wherein each end of the at least one plate is configured for selective connection of a friction fit connector of a CT lead thereto.
 36. The electrical power meter according to claim 33, wherein the at least one plate is fabricated from nickel plated brass.
 37. The electrical power meter according to claim 30, wherein the housing comprises at least one aperture configured for mounting by a rail shaped support member.
 38. The electrical power meter according to claim 30, wherein the housing comprises at least one aperture configured for mounting by an L shaped support member.
 39. The electrical power meter according to claim 30, wherein the at least one passage is located along a side of the housing.
 40. The electrical power meter according to claim 30, wherein the electrical power meter is configured for connection as at least one of a three-phase, four-wire system wye with direct voltage, 3 element; a three-phase, four-wire system wye with direct voltage, 2.5 element; a three-phase, four-wire wye with PTs, 3 element; a three-phase, four-wire wye with PTs, 2.5 element; a three-phase, three-wire delta with direct voltage; and a three-phase, three-wire delta with PTs.
 41. The electrical power meter according to claim 30, wherein at least one of a top surface and a bottom surface of the housing is configured to selectively receive a mounting bracket.
 42. The electrical power meter according to claim 30, wherein the at least one current input further comprises a toroid sensor coupled to the electrical circuitry for measuring power usage.
 43. An electrical power meter comprising: a housing for containing electrical circuitry for measuring power usage therein, the housing including at least one voltage input and at least one current input, the at least one current input being configured as at least one passage extending entirely through the housing, wherein the at least one passage is configured to receive at least one CT lead therethrough and the at least one current input measures an amount of current in the at least one CT lead, and wherein said at least one CT lead extends through the at least one passage of the housing un-connected to any electrical component of said electrical circuitry for measuring power usage.
 42. The electrical power meter according to claim 30, wherein the at least one current input measures an amount of current in the at least one CT lead.
 44. An electrical power meter comprising: a housing for containing electrical circuitry for measuring power usage therein, the housing including at least one voltage input and at least one current input, the at least one current input being configured as at least one passage extending entirely through the housing, wherein the at least one passage is configured to receive at least one elongate, electrically conductive plate configured for selective positioning within the at least one passage of the housing, each at least one plate includes a first end and a second end extending from the at least one passage of the housing when the at least one plate is positioned therein, each end of the at least one plate is configured for selective connection of a CT lead thereto, wherein the at least one plate extends through the at least one passage of the housing un-connected to any electrical component of said electrical circuitry for measuring power usage.
 45. The electrical power meter according to claim 44, wherein each end of the at least one plate is configured for selective connection of a lug of a CT lead thereto.
 46. The electrical power meter according to claim 44, wherein each end of the at least one plate is configured for selective connection of a friction fit connector of a CT lead thereto.
 47. The electrical power meter according to claim 44, wherein the at least one current input measures an amount of current in the at least one CT lead.
 48. The electrical power meter according to claim 44, wherein the at least one current input further comprises a toroid sensor coupled to the electrical circuitry for measuring power usage.
 49. An electrical power meter comprising: a housing for containing electrical circuitry for measuring power usage therein, the electrical circuitry including a digital sampler configured for sampling at least one voltage waveform and at least one current waveform and a processor configured to generate power consumption information from the at least one voltage and current waveforms; wherein the housing includes at least one voltage input and at least one current input coupled to the digital sampler, the at least one current input being configured as at least one passage extending entirely through the housing, wherein the at least one passage is configured to receive at least one CT lead therethrough, and wherein said at least one CT lead extends through the at least one passage of the housing un-connected to any electrical component of said electrical circuitry for measuring power usage. 